Response:

Abstract

We appreciate the interest shown by Drs Triantafyllou, Tziatzios, and Gkolfakis1Triantafyllou K. Tziatzios G. Gkolfakis P. Meta-analysis evaluating colonoscopy novelties: mind the methodology!.Gastrointest Endosc. 2018; 88: 576-577Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar in our article2Castaneda D. Popov V.B. Verheyen E. et al.New technologies improve adenoma detection rate, adenoma miss rate and polyp detection rate: a systematic review and meta-analysis.Gastrointest Endosc. 2018; 88: 209-222Abstract Full Text Full Text PDF PubMed Scopus (36) Google Scholar and consider their comments appropriate. As mentioned in the letter, in our analysis we used data from parallel and crossover studies, which directly evaluated the adenoma detection rate (ADR) and adenoma miss rate (AMR), respectively. For the ADR analysis, we included data from crossover studies for the final calculation, obtaining the raw data from the first pass in both arms to establish the ADR in each study, which essentially followed the ADR calculation principle used in the parallel studies. As we acknowledged in the limitations section of our manuscript, the detection rates in all the studies investigating the performance of “colonoscopy novelties” have an inherent observer bias because the endoscopists cannot be blinded when using the technologies. We extensively compared our data extraction (used for the calculations and forest plot graph construction) and the data presented in Table 1 of our article. We detected a misprint in the table for the study by De Palma et al,3De Palma G.D. Giglio M.C. Bruzzese D. et al.Cap cuff-assisted colonoscopy versus standard colonoscopy for adenoma detection: a randomized back-to-back study.Gastrointest Endosc. 2018; 87: 232-240Abstract Full Text Full Text PDF PubMed Scopus (43) Google Scholar in which the new technology devices (NTD) AMR was 1.1% instead of 10%. The data presented in the rest of the table are correct, as are the results presented in the forest plot. Meta-analysis evaluating colonoscopy novelties: mind the methodology!Gastrointestinal EndoscopyVol. 88Issue 3PreviewHaving read with interest the meta-analysis that examined the effects of technologic novelties in improving the adenoma detection rate (ADR) and adenoma miss rate (AMR) in colonoscopy,1 we noted that the authors combined in the analysis data from randomized and nonrandomized studies and pooled outcomes data from different study designs. Although the former practice is debatable, combining studies with different designs (parallel groups vs crossover) that measure different outcomes (ADR vs AMR) to calculate the effect size of ADR is questionable2; thus, the results of ADR effect size should be interpreted cautiously, in our opinion. Full-Text PDF